mysql与varchar字段连接

Question

我需要加入2个表

a）table_a

id        ref_no                        name
---------------------------------------------------
1       HRTU/00000001/2013             ram
2       HRTU/00000002/2013             sam

b）table_b

       ref_no                        desg
---------------------------------------------------
    HRTU/00000001/2013               project manager
    HRTU/00000002/2013               developer

这两个表将由他们的ref_no连接。并会给我输出如下

c）output_table

 ref_no                              name                             desg
----------------------------------------------------------------------------------
    HRTU/00000001/2013               ram                       project manager
    HRTU/00000002/2013               sam                         developer

Answer 1

SELECT a.*, b.*  -- SELECT columns you want
FROM    table1 a
        INNER JOIN table2 b
            ON a.ref_no = b.ref_no

• SQLFiddle Demo

要充分了解联接知识，请访问以下链接：

• Visual Representation of SQL Joins

Answer 2

SELECT a.ref_no AS ref_no, a.valp AS name, b.desg AS desg
FROM table1 a
INNER JOIN table2 b ON a.ref_no = b.ref_no

在SELECT中使用“AS”可以给出列名